from OpManager import settings
import pymysql
from DBUtils.PooledDB import PooledDB

# sqlconn = pymysql.connect(settings.mysql['ip'], settings.mysql['user'], settings.mysql['passwd'],
#                           settings.mysql['database'])
# sqlconn.ping(True)
# cursor = sqlconn.cursor()


POOL = PooledDB(
    creator=pymysql,  # 使用链接数据库的模块
    maxconnections=None,  # 连接池允许的最大连接数，0和None表示不限制连接数
    mincached=0,  # 初始化时，链接池中至少创建的空闲的链接，0表示不创建
    maxcached=0,  # 链接池中最多闲置的链接，0和None不限制
    maxshared=0,  # 链接池中最多共享的链接数量，0和None表示全部共享。PS: 无用，因为pymysql和MySQLdb等模块的 threadsafety都为1，所有值无论设置为多少，_maxcached永远为0，所以永远是所有链接都共享。
    blocking=True,  # 连接池中如果没有可用连接后，是否阻塞等待。True，等待；False，不等待然后报错
    maxusage=1,  # 一个链接最多被重复使用的次数，None表示无限制
    setsession=[],  # 开始会话前执行的命令列表。如：["set datestyle to ...", "set time zone ..."]
    ping=0,
    # ping MySQL服务端，检查是否服务可用。
    # 如：0 = None = never,
    # 1 = default = whenever it is requested,
    # 2 = when a cursor is created,
    # 4 = when a query is executed,
    # 7 = always
    host=settings.mysql['ip'],
    port=3306,
    user=settings.mysql['user'],
    password=settings.mysql['passwd'],
    database=settings.mysql['database'],
    charset='utf8'
)


def MysqlPool(sql, num):
    # 执行sql
    conn = POOL.connection()
    cursor = conn.cursor(pymysql.cursors.DictCursor)
    cursor.execute(sql)
    # 获取单条数据
    if num == 1:
        result = cursor.fetchone()
    elif num == 99:
        result = cursor.fetchall()
    elif num == 0:
        conn.commit()
        result = "执行成功"
    else:
        result = cursor.fetchmany(num)
    conn.close()
    cursor.close()
    return result
